package cn.flightfeather.thirdappmodule.view;
|
|
import android.animation.ObjectAnimator;
|
import android.animation.ValueAnimator;
|
import android.annotation.SuppressLint;
|
import android.content.Context;
|
import android.util.AttributeSet;
|
import android.view.MotionEvent;
|
import android.view.View;
|
import android.view.ViewGroup;
|
import android.widget.ScrollView;
|
|
public class HeadZoomScrollView extends ScrollView {
|
public HeadZoomScrollView(Context context) {
|
super(context);
|
}
|
|
|
public HeadZoomScrollView(Context context, AttributeSet attrs) {
|
super(context, attrs);
|
}
|
|
|
public HeadZoomScrollView(Context context, AttributeSet attrs, int defStyleAttr) {
|
super(context, attrs, defStyleAttr);
|
}
|
|
|
//用于记录下拉位置
|
private float y=0f;
|
//zoomView原本的宽高
|
private int zoomViewWidth = 0;
|
private int zoomViewHeight = 0;
|
//是否正在放大
|
private boolean mScaling = false;
|
//放大的view，默认为第一个子view
|
private View zoomView;
|
public void setZoomView(View zoomView) {
|
this.zoomView = zoomView;
|
}
|
//滑动放大系数，系数越大，滑动时放大程度越大
|
private float mScaleRatio = 0.4f;
|
public void setmScaleRatio(float mScaleRatio) {
|
this.mScaleRatio = mScaleRatio;
|
}
|
//最大的放大倍数
|
private float mScaleTimes = 2f;
|
public void setmScaleTimes(int mScaleTimes) {
|
this.mScaleTimes = mScaleTimes;
|
}
|
//回弹时间系数，系数越小，回弹越快
|
private float mReplyRatio = 0.5f;
|
public void setmReplyRatio(float mReplyRatio) {
|
this.mReplyRatio = mReplyRatio;
|
}
|
|
|
@SuppressLint("NewApi")
|
@Override
|
protected void onFinishInflate() {
|
super.onFinishInflate();
|
// 不可过度滚动，否则上移后下拉会出现部分空白的情况
|
setOverScrollMode(OVER_SCROLL_NEVER);
|
// 获得默认第一个view
|
if (getChildAt(0) != null && getChildAt(0) instanceof ViewGroup && zoomView == null) {
|
ViewGroup vg = (ViewGroup) getChildAt(0);
|
if (vg.getChildCount() > 0) {
|
zoomView = vg.getChildAt(0);
|
}
|
}
|
}
|
|
|
@Override
|
public boolean onTouchEvent(MotionEvent ev) {
|
if (zoomViewWidth <= 0 || zoomViewHeight <=0) {
|
zoomViewWidth = zoomView.getMeasuredWidth();
|
zoomViewHeight = zoomView.getMeasuredHeight();
|
}
|
if (zoomView == null || zoomViewWidth <= 0 || zoomViewHeight <= 0) {
|
return super.onTouchEvent(ev);
|
}
|
switch (ev.getAction()) {
|
case MotionEvent.ACTION_MOVE:
|
if (!mScaling) {
|
if (getScrollY() == 0) {
|
y = ev.getY();//滑动到顶部时，记录位置
|
} else {
|
break;
|
}
|
}
|
int distance = (int) ((ev.getY() - y)*mScaleRatio);
|
if (distance < 0) break;//若往下滑动
|
mScaling = true;
|
setZoom(distance);
|
return true;
|
case MotionEvent.ACTION_UP:
|
mScaling = false;
|
replyView();
|
break;
|
}
|
return super.onTouchEvent(ev);
|
}
|
|
|
/**放大view*/
|
private void setZoom(float s) {
|
float scaleTimes = (float) ((zoomViewWidth+s)/(zoomViewWidth*1.0));
|
// 如超过最大放大倍数，直接返回
|
if (scaleTimes > mScaleTimes) return;
|
|
|
ViewGroup.LayoutParams layoutParams = zoomView.getLayoutParams();
|
layoutParams.width = (int) (zoomViewWidth + s);
|
layoutParams.height = (int)(zoomViewHeight*((zoomViewWidth+s)/zoomViewWidth));
|
// 设置控件水平居中
|
((MarginLayoutParams) layoutParams).setMargins(-(layoutParams.width - zoomViewWidth) / 2, 0, 0, 0);
|
zoomView.setLayoutParams(layoutParams);
|
}
|
|
|
/**回弹*/
|
@SuppressLint("NewApi")
|
private void replyView() {
|
final float distance = zoomView.getMeasuredWidth() - zoomViewWidth;
|
// 设置动画
|
ValueAnimator anim = ObjectAnimator.ofFloat(distance, 0.0F).setDuration((long) (distance * mReplyRatio));
|
anim.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
|
@Override
|
public void onAnimationUpdate(ValueAnimator animation) {
|
setZoom((Float) animation.getAnimatedValue());
|
}
|
});
|
anim.start();
|
}
|
|
|
@Override
|
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
|
super.onScrollChanged(l, t, oldl, oldt);
|
if (onScrollListener!=null) onScrollListener.onScroll(l,t,oldl,oldt);
|
}
|
|
|
private OnScrollListener onScrollListener;
|
public void setOnScrollListener(OnScrollListener onScrollListener) {
|
this.onScrollListener = onScrollListener;
|
}
|
|
|
/**滑动监听*/
|
public interface OnScrollListener{
|
void onScroll(int scrollX,int scrollY,int oldScrollX, int oldScrollY);
|
}
|
}
|
